Emulsion aggregation (EA) toners are used in forming print and/or electrophotographic images. Emulsion aggregation techniques may involve the formation of a polymer emulsion by heating a monomer and undertaking a batch or semi-continuous emulsion polymerization, as disclosed in, for example, U.S. Pat. Nos. 5,853,943, 5,290,654, 5,278,020, 5,308,734, 5,344,738, 6,593,049, 6,743,559, 6,756,176, 6,830,860, 7,029,817 and 7,329,476, and U.S. Publ. Nos. 2006/0216626, 2008/0107989, 2008/0107990, 2008/0236446 and 2009/0047593. The disclosure of each of the foregoing documents hereby is incorporated by reference in entirety.
Polyester EA ultra low melt (ULM) toners are prepared utilizing amorphous and crystalline polyester resins as illustrated, for example, in U.S. Publ. No. 2008/0153027, the disclosure of which is hereby incorporated by reference in entirety.
Current ULM polyester-based toners result in a minimum fusing temperature (MFT) reduction of about 20° C. as compared to that of standard toners, and that enables lower fuser energy, which translates to increased device longevity. The reduction of MFT is achieved by the introduction of a crystalline resin in amounts from about 5 to about 10%. Although adding more crystalline resin (about 10 to about 20%) reduces the MFT further, the crystalline properties, i.e., conductivity, degrade electrical performance.
Thus, reduction of the MFT of toners without degradation of the electrical performance of toners remains desirable.